Narrative:

I'm writing this to make you aware of an incident that occurred in ZZZ MOA today. The incident occurred at approximately [time] while supporting [government entity] operations in the southeast corner of the MOA. I was the pilot not flying in the right seat. We had two-way comms with the airspace controlling facility and had made them aware of our position; which they relayed to the other aircraft that entered the MOA. After being established in a 2 mile radius; right-hand orbit at 12;500 feet over that point for roughly 30 minutes; we observed a TCAS track that was approximately 7 miles away; 500 feet below; 2 to 3 o'clock; closing and climbing. I attempted to visually acquire the aircraft while pilot flying monitored the TCAS scope. The track became a traffic advisory at approximately 3 miles and 400 feet below; and within 2-3 seconds; a resolution advisory that directed us to not descend; then into an aural 'climb climb' alert. The pilot flying began a climb to comply with the RA at which point I visually acquired a single military fighter and we exchanged aircraft control. I reversed from the climb into an aggressive descent to avoid the fighter. During that maneuver; pilot not flying visually acquired the fighter as it passed over us (my estimate is within 200 feet). The belly of the aircraft was all we could see; so no tail flash was observed. TCAS indicated a two-ship after this; but we only visually acquired one. It's possible that the RA was generated by the other aircraft (if it was below us); or that their close in low to high maneuver prevented the TCAS from computing a proper escape maneuver. After stabilizing the aircraft; we opted to break station; depart the MOA and return to base.

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Original NASA ASRS Text

Title: A pilot orbiting in a MOA reported a NMAC with a fighter jet.

Narrative: I'm writing this to make you aware of an incident that occurred in ZZZ MOA today. The incident occurred at approximately [time] while supporting [Government entity] operations in the southeast corner of the MOA. I was the pilot not flying in the right seat. We had two-way comms with the airspace controlling facility and had made them aware of our position; which they relayed to the other aircraft that entered the MOA. After being established in a 2 mile radius; right-hand orbit at 12;500 feet over that point for roughly 30 minutes; we observed a TCAS track that was approximately 7 miles away; 500 feet below; 2 to 3 o'clock; closing and climbing. I attempted to visually acquire the aircraft while Pilot Flying monitored the TCAS scope. The track became a traffic advisory at approximately 3 miles and 400 feet below; and within 2-3 seconds; a resolution advisory that directed us to not descend; then into an aural 'CLIMB CLIMB' alert. The Pilot Flying began a climb to comply with the RA at which point I visually acquired a single military fighter and we exchanged aircraft control. I reversed from the climb into an aggressive descent to avoid the fighter. During that maneuver; Pilot Not Flying visually acquired the fighter as it passed over us (my estimate is within 200 feet). The belly of the aircraft was all we could see; so no tail flash was observed. TCAS indicated a two-ship after this; but we only visually acquired one. It's possible that the RA was generated by the other aircraft (if it was below us); or that their close in low to high maneuver prevented the TCAS from computing a proper escape maneuver. After stabilizing the aircraft; we opted to break station; depart the MOA and return to base.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.